Affiliations: [a] Departamento de Estructura de la Materia, Física Térmica y Electrónica, Universidad Complutense de Madrid (UCM), Facultad de Ciencias Físicas, Madrid, Spain
| [b] Department of Experimental Psychology, Faculty of Psychology, Complutense University of Madrid (UCM), Madrid, Spain
| [c] Center for the Prevention of Cognitive Impairment (Madrid Salud), Madrid City Council, Madrid, Spain
| [d] Neurology Department, Clinic San Carlos Hospital, Madrid, Spain
Correspondence:
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Correspondence to: Isabel Suárez-Méndez, Departamento de Estructura de la
Materia, Física Térmica y Electrónica, Universidad Complutense de Madrid (UCM), Facultad de Ciencias Físicas, Plaza de Ciencias 1, E-28040, Madrid, Spain. E-mail: isabel.suarez@ucm.es.
Abstract: Background:Recent studies demonstrated that brain hypersynchrony is an early sign of dysfunction in Alzheimer’s disease (AD) that can represent a proxy for clinical progression. Conversely, non-pharmacological interventions, such as cognitive training (COGTR), are associated with cognitive gains that may be underpinned by a neuroprotective effect on brain synchrony. Objective:To study the potential of COGTR to modulate brain synchrony and to eventually revert the hypersynchrony phenomenon that characterizes preclinical AD. Methods:The effect of COGTR was examined in a sample of healthy controls (HC, n = 41, 22 trained) and individuals with subjective cognitive decline (SCD, n = 49, 24 trained). Magnetoencephalographic activity and neuropsychological scores were acquired before and after a ten-week COGTR intervention aimed at improving cognitive function and daily living performance. Functional connectivity (FC) was analyzed using the phase-locking value. A mixed-effects ANOVA model with factors time (pre-intervention/post-intervention), training (trained/non-trained), and diagnosis (HC/SCD) was used to investigate significant changes in FC. Results:We found an average increase in alpha-band FC over time, but the effect was different in each group (trained and non-trained). In the trained group (HC and SCD), we report a reduction in the increase in FC within temporo-parietal and temporo-occipital connections. In the trained SCD group, this reduction was stronger and showed a tentative correlation with improved performance in different cognitive tests. Conclusion:COGTR interventions could mitigate aberrant increases in FC in preclinical AD, promoting brain synchrony normalization in groups at a higher risk of developing dementia.
